How did Mazda screw this up so bad?
I have mentioned this before in a prior post (not in this thread), but these forums are a great place because they allow people who are interested in learning about a car or brand to have an additional resource to draw from. They also serve as a repository of issues and resolutions. Anyone who might be having an issue with their car will likely find that it has been discussed here with others who have had/are having the same issue. This means that when a solution is found, that info is shared with the community. However, this also makes it seem like an issue is more common than it actually is.
Mazda's reputation for reliability has been improving greatly in recent years, to the point that they're in some conversations with Toyota and Lexus for overall reliability. If you are concerned that your car may develop the issue, the best thing you can do is either plan for it (by setting up an emergency repair fund), or sell the car and hope that your next vehicle is better.
What I'm doing is setting up a repair fund. My powertrain is under warranty for another year. I'll start putting money away every month or so, enough so that by the time warranty runs out, I'll have enough to cover a potential repair. If I need to have the engine repaired, I'll be prepared for the cost, which would result in a new engine that doesn't have the issue. If I never end up needing the repair, then I have a nice chunk of change for maintenance purposes, or to use towards a deposit on a new vehicle. The best part about this plan is that even in the worst case scenario, there is a solution, and that means I can continue to drive and enjoy my car, relatively worry-free.